SAT practice problems

Question

1.) Graphene, which is used in the manufacture of integrated circuits, is so thin that a sheet weighing one ounce can cover up to 7 football fields. If a football field had an area of approximately 1 and 1/3 acres, about how many acres could 48 ounces of graphene cover?

A) 250

B) 350

C) 450

D) 1350

2.) If 3/5w = 4/3, what is the value of w?

Answer 1

If 1 ounce covers 7 football fields, then 48 ounces covers 48 * 7 = 336 football fields

Since each football field is 1 1/3 or 4/3 acres, 48 ounces would cover 336 * 4/3 = 448 acres.

3 = 4

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5w 3

cross multiply:

5w * 4 = 3 * 3

20w = 9

w = 9/20

w = 4/9